The present invention relates, in general, to flat panel image displays, and more particularly to solid-state structures for generating bright, luminous pixels which may be used, for example, to produce images on flat panel surfaces.
Conventional cathode ray tubes utilize a scanning electron beam from an electron gun to impinge on phosphors on a display screen. The electron beam causes the phosphors to release light which is transmitted through the screen to the viewer. Such screens are widely used, but since they are relatively large and utilize relatively high voltages and complex control circuitry, they are not suitable for many applications.
Flat panel displays have been developed which combine the phosphor technology of cathode-ray tubes with integrated circuit technology to create thin, high-resolution displays wherein each pixel is activated by its own electron emitter. This type of display is becoming increasingly important in appliances requiring lightweight portable image display screens. However, such devices require a relatively high voltage differential between the cathode emitting surface and the phosphor-coated display screen surface. Since these surfaces must be close together in order to maintain the desired structural thinness and the high image resolution required in such display devices, problems of electrical breakdown are encountered. Furthermore, such devices must be operated under a vacuum, and the high pressure differential that exists between external atmospheric pressure and the pressure within the evacuated chamber creates additional problems. Thus, there is a need for an improved structure and method for obtaining bright, luminous pixels in flat panel displays while eliminating the complex phosphors, the high vacuum, high voltage requirements, and the complex beam control circuits required in prior devices.